Method of producing lead alloys



Patented Jan. 4, 1938 UNITED STATES 2,104,444 METHOD OF PRODUCING LEAD ALLOYS Frederic W. Willard, Summit, N. 3., assignor to Nassau Smelting and Refining Company, New York, N. Y., a' corporation of New York No Drawing.

Application December 12, 1934, Serial No. 757,123

9 Claims. (on. 75-135 This invention relates to a method of producing lead alloy and more particularly to a method oi incorporating copper in lead.

The superior physical characteristics of South- 6 eastern Missouri lead due to the presence of small amounts of other metals have long been recognized. Processes employed for the extracin copper in desilverlzed lead is particularly disadvantageous when lead is employed in the manuiacture of cable sheaths. The extrusion qualiu tie's oi lead alloy employed for this purpose are markedly improved by the presence of approximately .06 per, cent copper. Then, too, copperlead alloys are frequently required which are not contaminated with undesirable materials produced in the alloy by the metals or metallic compounds added to produce the alloys or formed during the process. The slight solubility of cop-' per in lead and the relatively high melting point or, copper renders diiilcult the formation of a copper-lead alloy by mixing the constituent elements directly.

An object 01' this invention is to form a synthetic copper-lead alloy at temperatures below the melting point of copper.

A more particular object oi. this invention is to produce a copper-lead alloy economically from desilverized lead, without deleterious contamination, which possesses the desirable extrusion qualities oi Southeastern Missouri lead.

in accordance with this invention, copper compounds of organic acids are added to a molten 4g bath of lead or lead alloy to form a copper-lead ailoy substantially free from contamination. The leader lead alloy is gradually raised to above its melting point after the copper compound of the organic acid is added or a molten bath of 5 leador lead alloy is subjected to the action of a. copper compound of an organic acid. In either procedure the copper compound of the organic acid is usually decomposed to form metallic copper which is,quickly dispersed through so out the lead. when these compounds decompose, they tend to prevent the formation of oxides oi the metals contained in the bath. As

a consequence, the incorporation of copper in the lead is rapid and substantially quantitative 55 for small amounts of copper in lead.

If a lead alloy containing approximately .06 per cent copper is desired, copper acetate in an amount equivalent to .06 per cent of copper in the resulting alloy is added to a molten bath of lead between the melting point of the lead or 5 lead alloy and about 600 C. The metallic copper formed is quickly dispersed throughout the lead or lead alloy.

Another procedure is to prepare an antimony copper alloy by subjecting a molten bath of antimony maintained between the melting point of antimony and 100 higher to the action of a copper compound of an organic acid, such as copper carbonate, and then adding the resulting copper antimony alloy to a molten bath of lead. In this procedure the amount of the compound of the organic acid is equivalent to the desired quantity of copper to be incorporated in the alloy.

'The advantages of preparing copper lead or copper antimony lead alloys by the above described methods are that rapid incorporation of copper in the lead results and that for small quantities of copper in lead, since the action is quantitative, no problem of adding an excessive amount of copper compound arises. -Furthermore, copper compounds of organic acids are obtainable commercially in relatively pure form and the resulting copper-lead alloy is substantially free from deleterious contamination.

While copper acetates and copper carbonates were employed in illustrating this invention, other copper compounds of organic acids may be used. For example, copper compounds of monocarboxylic acids suchas those of formic, propionic, butyric palmitic and stearic acid or of dicarboxylic acids such as those of oxalic, succinic and malonic acid or of hydroxy acid such as those of tartaric and malic acids or of arcmatic carboxylic acids such as those of benzoic, cinnamic or phthalic acid may be employed in like'manner. The procedure followed when copper compounds of these acids are used is the same as that described above for the use of the copper compounds of acetic or carbonic acids.

While preferred embodiments of this invention have been described, modifications therein may per throughout the lead without the formation of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic compound comprising a car- I boxyl radical.

2. A method of forming a. copper-lead allo comprising adding a copper compound of a carboxylic acid to lead at a temperature above the melting point of said lead under such conditionscopper compound of an aliphatic carboxylic acid under such conditions to effect dispersion of the copper throughout the lead without the formation of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic compound of an aliphatic carboxylic acid.

.. 4. A method of forming copper-lead alloy comprising adding a copper compound of an arcmatic carboxylic acid to a molten bath of lead under such conditions to efiect dispersion of the copper throughout the lead without the forma tion of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic compound of an aromatic carboxylic acid.

5. A method of alloying copper with lead com- 4 out the formation of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic acetate.

6. A method of preparing acopper-lead alloy comprising adding copper carbonate to a molten Bath 07 lead under such conditions to effect the dispersion of copper throughout the lead without the formation of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic carbonate. 1. A method of preparing a copper-lead alloy comprising adding a compound of copper which decomposes at a temperature below the melting point of lead to a molten bath of lead whereby metallic copper is dispersed throughout said lead without the formation of an oxide of copper.

8. A method of preparing a copper-lead alloy comprising subjecting a bath of lead, maintained at a temperature between approximately 327 C. and 600 C., to the action of cupric acetate in an amount equivalent to .06 per cent copper of the lead in said bath under such conditions to efiect the dispersion of copper throughout the lead without the formation of an oxide of copper and to form an uncontaminated copper-lead alloy which is substantially free of any metallic acetate.

9. A method of preparing an uncontaminated copper lead alloy comprising subjecting a molten hath 01. lead to the action of a copper compound of an organic acid under such condition to etiect dispersion of the copper throughout said lead without the formation of an oxide of copper and to form an uncontaminated lead copper alloy which is substantially free of any metallic compound of an organic acid.

FREDERIC W. 

